Aspects described herein generally relate to activating single wire protocol (SWP) communications within a wireless device and specifically to improving activation of the SWP communications.
Advances in technology have resulted in smaller and more powerful personal computing devices. For example, there currently exist a variety of portable personal computing devices, including wireless computing devices, such as portable wireless telephones, personal digital assistants (PDAs) and paging devices that are each small, lightweight, and can be easily carried by users. More specifically, the portable wireless telephones, for example, further include cellular telephones that communicate voice and data packets over wireless networks. Many such cellular telephones are being manufactured with relatively large increases in computing capabilities, and as such, are becoming tantamount to small personal computers and hand-held PDAs. Further, such devices are being manufactured to enable communications using a variety of frequencies and applicable coverage areas, such as cellular communications, wireless local area network (WLAN) communications, near-field communications (NFC), etc.
NFC can be used for secured communications in a device equipped with a universal integrated circuit card (UICC) where the device may activate a contactless frontend (CLF) that connects to the UICC to provide the secured communications. SWP is used as the interface between the CLF and UICC in a device such that the CLF activates a pin of the UICC as the single wire input/output (SWIO) to provide an energy (e.g., voltage) thereto, along with a transmission clock, and/or other signals for bus management. Data to be transmitted to/from the UICC using SWP is represented by binary states of voltage and current on the single wire.
Activation procedures for SWP between the CLF and UICC in a device involve various frames transmitted between the CLF and UICC. It is possible, however, that one or more frames of the activation procedure are not properly sent or received between the CLF and UICC.